Dave's Glossary of Construction Terms by Dave Osborne (www.daveosborne.com) 5/4" A thickness of decking material between 1 x 6 and 2 x 6. Although it is called 5/4 x 6, it is actually 1" thick and 5 1/2" wide. Likewise, a 1 x 6 is really 3/4" thick and a 2 x 6 is 1 1/2" thick. Barge Board The exterior finish nailed to the side of the end rafter or truss of a gable roof. Bird's Mouth See Seat Cut Building Code An official list of rules that a building or construction site is legally obliged to follow. Building Codes are generally state, province or country wide but local governments can add their own rules. The rules in Building Codes are generally well thought out and have a practical reason behind them. Even if there is no legal obligation for someone to follow Building Codes, it is still a very good idea to know and use them. Crown Almost every board is curved slightly. The crown is the top of the curve of a board.
Dwelling Unit A suite operated as a housekeeping unit, used or intended to be used as a domicile by one or more persons and usually containing cooking, eating, living, sleeping and sanitary facilities. Face Nailed Nailing through the face of a board, as opposed to nailing through the spline of a board or toe nailing on an angle. Fascia Board The exterior finish nailed to the trimmer that is nailed to the rafter or truss ends that run horizontally around the roof on which the gutters are mounted. Framing Square See Steel Square. Gable The upper triangular-shaped portion of the end wall of a house. Gable End The entire end wall of a house formed from the pitch of the roof. Gable Truss The end truss in a roof system that caps the end wall. If the overhang is more than 16", the gable truss is lowered by 3 1/2" to allow for 2x4's to be cantilevered
over this truss and nailed into the adjoining one to form the overhang. G1S "Good One Side" This is a quality of plywood that has one of its sides smooth enough to look good when painted or wallpapered. It would be used where only its good side will be visible. G2S "Good Both Sides" This is a quality of plywood that has both of its sides smooth enough to look good when painted or wallpapered. It's more expensive than G1S and so is used only where both sides of the plywood will be visible. Gusset A panel or bracket of wood or metal fastened to the intersections of members or at corners to provide strength and stiffness. Header A horizontal structural member that supports the load over a window or door opening. Also known as a lintel. Joist One of a group of structural members designed to support a floor or ceiling load. When the member supports a ceiling as well as a roof it is called a roof joist. Joist Hanger A steel section shaped like a stirrup, which is specially bent so it can be fastened to a beam in order to provide end support for joists, headers, etc.
Lintel A horizontal structural member that supports the load over a window or door opening. Also known as a header. Nail Set A punch used to drive in the head of a nail so it's slightly below or level with a surface. If you just have one or two nails to set, another nail turned upside down can substitute for a nail set. But, be careful the upturned nail doesn't slide off the nail you're trying to set and make a larger hole. Nosing The part of the step that sticks out past the riser. Ogee An S-shaped curve or an arch formed of two S-shaped curves meeting at the top of the arch. Pitch of a Roof See Rise (2) Plate Any of the following: Top plate: A horizontal member placed on a wall and supported on studs to carry the trusses or rafters of a roof or the joists of a floor. The double plate is nailed on this top plate to facilitate overlapping of joints of the top plate at corners and intersections. Bottom Plate: A horizontal member on which the studs of a
wall sit, providing a means of attachment to the foundation or floor. Plate Line A line scribed or marked on a rafter that corresponds to the outside face of the wall. Plumb Verticle. Straight up and down. (See following) Plumb Bob A weight that has a string connected to the center of its top. It's used mostly to ensure that a wall being constructed is perfectly verticle. It can also be used to get an exact measurement of a spot directly below whatever it is hanging down from. Example: hang a plumb bob from a ceiling fixture and measure from the bob to the wall to get the exact distance the fixture is from that wall. Rafter The slanting boards that give the roof its slope and support. They are like wall studs except they are slanted for the roof. Ribbon A board or length of boards nailed to wall studs with the purpose of supporting ceiling joists nailed to the ribbon. Ridge Board The board that runs along the top of all the rafters of a roof and holds them in place.
Rip To saw a board or plywood in the same direction as the grain of the wood. To cut a board, on the other hand, refers to cutting it across the grain. Although plywood is made up of layers of veneer, each placed with the direction of its grain perpendicular to the layer below it, plywood does have grain. We refer to the top and bottom veneers when we talk about the grain of plywood. These outside veneers are what chip if we use a ripping saw for cross cutting. A ripping blade is different than a cross cut blade. A rip blade has teeth like chisels flat across where a cross cut blade has pointed teeth to cut the grain. Nowadays we use combination blades that do both, hence the name. That's why, before the days of power saws, a carpenter had both a rip saw and a crosscut saw. Rise 1) The height of one stair in a staircase. This is the amount of verticle distance someone moves when he or she steps from one stair onto the next. Per most Building Codes, the rise should be between 5 inches and 7 7/8 inches with the ideal rise for a residence being 7 inches. 2) With a roof, the rise is the verticle distance between the top of a section of roof and its lower edge. The section being measured always has a run (horizontal distance) of one foot (12"). The rise is used with the run to describe the pitch of the roof, for example if the roof rises 5" with each foot of run, it's called a 5 and 12 pitch. If the roof rises 7" with each foot of run, it's called a 7 and 12 roof. Riser The verticle part of a stair.
Run 1) With stairs: The horizontal distance of one stair in a staircase. It is how far "in" the stair goes which gives the amount of room for someone's foot as he or she climbs the stairs. Per most Building Codes, the run should be between 8¼ inches and 14 inches. An intermediate run is 11 inches. See tread for comparison to run. 2) With a roof, the run is the horizontal distance of a section of roof, compared to the rise, which is the verticle distance of that same section. When measuring the pitch of a roof the run is one foot. See also rise. S1S2E "Surfaced One Side Two Edges" This is a board, usually cedar, with both edges smooth and one side smooth. The remaining side is rough and this side is usually considered the good side, the side that's showing. S4S "Surfaced Four Sides" This is a board that is smooth on all sides. This is mostly kiln-dried fir. Seat Cut Also called a bird's mouth. This is a notch cut in each rafter where the bottom part of the rafter rests on the top of the wall. Without this notch, there would be only a tip of the bottom edge of the rafter touching the top of the wall. The seat cut gives a broader surface to nail the rafter to the top of the wall and it also helps prevent the walls from spreading out from the weight of the roof. Set
To drive a nail so the top of its head is level with or just below the surface of the material the nail is embedded in. The nail is usually punched in with a nail set but, in a pinch, another nail turned upside down can be used as a nail set. Span of a Roof This is the entire horizontal distance across that a roof covers. This is usually twice the total run for a gable roof. There are factors where this is not the case, such as a shed roof or an unequally pitched gable roof. Stair Gauge These are little thumb screw clamps that you attach to the steel square (framing square) right at the point of your riser and run measurements. With these installed on the square you simply slide the square along the stringer rather than having to look at the measurements for every move down the stringer. Steel Square Also called a framing square. Used by carpenters to measure stair stringers and roof rafters. STK "Select Tight Knot" This is a board that has knots in it but the knots are tight rather than loose. Select means it's the best grade. Strapping Concrete Walls To apply boards to the concrete wall to allow drywall or panelling or whatever to be attached. Strapping the walls with 2x4's on edge allows you to insulate the walls before applying drywall, etc.
Stringer A stair stringer is one of the boards that hold each step in place. They run the length of a straight set of stairs (see Figure 1). Strongback A support attached to the top of ceiling joists to strengthen them, maintain spacing and keep them at the same level. Tack To nail on a board but leaving the head of the nail out far enough to be able to pull it out if the board later needs to be moved. Toe Nail A nail inserted at an angle into the side of a board to ensure it penetrates into a second board. This is usually done where the first board is too thick to give enough penetration when nailed through the face. Total Rise 1) With stairs: The total height of a staircase which extends from the lower level up to the surface of the upper level. A staircase built from one floor up to another floor has a total rise of exactly one storey. 2) With a roof: the total rise is the verticle distance from the top of the roof to the top of the walls.
Total Run 1) With stairs: the total run is the horizontal distance from a plumb bob hanging from the top of a staircase to the edge of its bottom step. It's the length of the floor space that is under a staircase. 2) With a roof: the total run is the horizontal distance from a plumb bob, hanging from the top of a roof, to the exterior wall. On typical roofs, the top of the roof is in the center of the building and the roof slopes down to the sides of the house with both sides of the roof having the same amount of slope. In this typical case, the total run of the roof is half the span, which is the entire horizontal distance from one side of the roof to the other at the top of the outside walls. Tread The horizontal distance of one stair in a staircase. It is the run plus the nosing. Per most Building Codes, the tread should be between 9¼ inches and 14 inches. An intermediate tread is 12 inches. Truss A structural unit made up of crosspieces to provide support, over large spans, for a roof or bridge. A truss is designed to give the most lift using the least amount of material so its own weight is minimized.